Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V09_5/V9_508.TXT

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Subject: SPACE Digest V9 #508

SPACE Digest                                      Volume 9 : Issue 508

Today's Topics:
            Moon landing nostalgia
                IAU circulars
         Re: Computers for the space station
             Empty file found in mailbox.
      NASA GIVES ASSISTANCE TO PRIVATE LAUNCH COMPANY!!
               space station computers
           Re: Re: Venus & the Greenhouse effect...
----------------------------------------------------------------------

ReSent-Message-ID: <[e-mail]>
ReSent-Date: Tue, 20 Jun 89 14:07:01 -0400 (EDT)
ReSent-From: Ted Anderson <[e-mail]>
ReSent-To: Space <[e-mail]>
Date: Sat, 17 Jun 89 18:25:06 CDT
From: "Bill Ball" <[e-mail]>
Subject: Moon landing nostalgia

Comments on two items celebrating the 20 anniversary of the Apollo 11
landing which I have come across recently:

Air & Space magazine June/July 1989.

A publication of the Smithsonian. The (almost) entire issue is devoted
to a variety of articles on the topic, most of them quite good (although
none quite as entertaining as the story of Howard Hughes' first flight
in the Lockheed Constellation found in the back of the issue). There is
more criticism of NASA than one might expect.

Man In Space A Time Television Special (60 min.)

Superb. The first 40 min. is a spellbinding review of the trip to
the moon with heavy (and IMHO entirely correct) emphasis on the story of
human endeavor rather than technological accomplishment. It, like the
Air & Space issue, brings home what a fluke the Apollo program
was--having more to due with the Bay of Pigs than with the exploration
of space. The last part of Man in Space somehow manages to cover every
argument about our continuing role in space which has been discussed on
this list in the past year including controversies over the shuttle, the
space station, a trip to mars, and a manned vs. an unmanned program.
How did they do all this in an hour? I don't know but it was *very*
impressive. A must see even if you don't spring for the commemorative
coins they are pushing in the commercials.

Bill Ball
Dept. Political Science
U. of Missouri - Columbia
[e-mail]

------------------------------

Date: 19 Jun 89 14:26:38 GMT
From: frooz!cfashap![e-mail]  (Bill Wyatt)
Subject: IAU circulars

>> International Astronomical Union (IAU) Circular 4767 - 1989 April 7
>
>PLEASE keep posting these!!! Does the IAU have any kind of BB where
>newly reported astronomical events, SN, Asteroids, etc are posted? That
>kind of information would be a data feast for us all.
>
>I usually have to dig through a number of publications to keep up with
>this kind of info.

This came up during the postings concerning SN1987A. The IAU circular
service is not free, although it is non-profit. It is run by Brian
Marsden, here at the Center for Astrophysics, as the `Central Bureau
for Astronomical Telegrams' and the `Minor Planet Center'. There are
generally one or two circulars per week.

As I mentioned in March of 1987, no one especially minds an occasional
reposting of a circular in response to a specific question, but for
steady access, the subscription is required. The telegram service is
used internationally for timely bulletins and information disbursal,
and the subscriptions are what keeps the service going, so please
don't undermine the system!

The cost for the circulars is US $4.50 per month or $7.50 per month if
you require an invoice. For double the above price (you also still get
the hardcopy), you can get remote login access to their computer
service.  It's a VMS microVax, accessable via at least SPAN and
TELENET that I know of and probably modems, too.

For further information, contact the CBAT at 617-495-7244 or write:
  Central Bureau for Astronomical Telegrams
  60 Garden Street
  Cambridge MA 02138


Bill Wyatt, Smithsonian Astrophysical Observatory
    UUCP :  {husc6,cmcl2,mit-eddie}!harvard!cfa!wyatt
    ARPA:   [e-mail]
    SPAN:   cfa::wyatt                 BITNET: wyatt@cfa

------------------------------

Date: 20 Jun 89 15:38:09 GMT
From: mailrus!jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Computers for the space station

In article <[e-mail]> [e-mail] (John Roberts) writes:
>In the debate on the choice of Ada for much of the software, I would like to
>point out that saying "Ada is undesirable because not many programmers I know
>program in Ada" is not entirely reasonable, because Ada is a young language...

Um, it's over a decade old, and is showing its age badly, actually...
--
You *can* understand sendmail, |     Henry Spencer at U of Toronto Zoology
but it's not worth it. -Collyer| uunet!attcan!utzoo!henry [e-mail]

------------------------------

Date: Sun, 1 Jan 70 0:0:0 EST
From: Message Server
Subject: Empty file found in mailbox.

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File name: /afs/andrew.cmu.edu/usr1/ota/.MESSAGES/mail/space/incoming/+IYbQPb200UkVMBLHVC.
Written by: user Ted Anderson (7997).
Date and time of file writing: Tue Jun 20 01:15:53 1989

------------------------------

Reply-To: mordor!rutgers!pnet01.cts.com![e-mail]
Date: Sat, 17 Jun 89 11:57:26 PDT
From: mordor!rutgers!pnet01.cts.com![e-mail] (Jim Bowery)
To: hplabs!hp-sde!hp-sdd!crash![e-mail]
Subject: NASA GIVES ASSISTANCE TO PRIVATE LAUNCH COMPANY!!

NASA, AMROC AGREE TO CRITICAL CHEMICAL EXCHANGE

>                                    .....NASA provided two drums
>(about 600 lbs.) of the chemical to AMROC.

Free world production capacity for hydrogen peroxide 882 million kg / year.

United States capacity: 226 million kg / year.

Current US consumption 150 million kg / year.

76 million kg / year unused US capacity.

Approximate wholesale value of 300kg H2O2 is a few hundred dollars.

NASA's budget last year was $10 billion.

NASA's budget increase to this year's $13 billion has enabled NASA to provide
this critically needed chemical to a private launch company.
---------------------------------------------------------------------------
Jim Bowery    Phone: [phone]
PO Box 1981                  Join the Mark Hopkins Society!
La Jolla, CA 92038   (A member of the Mark Hopkins family of organizations.)

UUCP: {cbosgd, hplabs!hp-sdd, sdcsvax, nosc}!crash!pnet01!jim
ARPA: crash!pnet01![e-mail]
INET: [e-mail]

------------------------------

Date: 20 Jun 89 22:53:07 GMT
From: mailrus!jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: space station computers

In article <[e-mail]> [e-mail] writes:
>... NASA should look to the future, not the past.
>
>A key point here is that none of this is very exotic - I have no doubt that
>such work is being done now in various places. NASA used to overpay to get
>components _past_ the state of the art, the antithesis of the Big Dumb Booster
>concept. Now, they're overpaying to get obsolete components, which combines
>the worst of both approaches.

In a lot of support hardware, actually, NASA has always been very conservative
and has deliberately used the previous generation of hardware when possible.
They do this for the same reason AT&T does it for switching systems:  maximum
reliability.  Being at the leading edge of the state of the art -- never mind
ahead of it -- tends to cost you a lot of reliability.  The attitude many PC
users have toward crashes would be grossly unacceptable for a computer center
on Earth, never mind one on a space station.

Mind you, one can argue -- I have, in other contexts -- that it's better to
design the system to recover from errors rather than avoid them in the first
place.  This massively reduces costs and lead times by permitting off-the-
shelf hardware (absolutely nothing on the space station is off the shelf,
not even the light bulbs).  There are only a very few systems which really
must be ultra-reliable because errors in them really are intolerable...
especially since the chance of error can never be 0 anyway.
--
NASA is to spaceflight as the  |     Henry Spencer at U of Toronto Zoology
US government is to freedom.   | uunet!attcan!utzoo!henry [e-mail]

------------------------------

Date: 19 Jun 89 18:58:14 GMT
From: hpfcdc![e-mail]  (Scott Bayes)
Subject: Re: Re: Venus & the Greenhouse effect...

> Did they consider a slingshot around the Sun to increase the terminal
> velocity?  Is that even possible?  (If you ain't got enough m, try some v^2).
> On the other hand, being closer to the Sun and more rigid, the tidal slowing
> effect might be embarrasingly large in the middle run...
>
>
> --
> John Woods, Charles River Data Systems, Framingham MA, [phone]
> ...!decvax!frog!john, [e-mail], ...!mit-eddie!jfw, [e-mail]
>     People...How you gonna FIGURE 'em?
>     Don't bother, S.L.--Just stand back and enjoy the EVOLUTIONARY PROCESS...

I don't believe you can slingshot from any body if you start within and
stay within that body's escape speed. We can slingshot from Jupiter, because
we start with more than enough E to escape its gravity well, and escape
with even more (having stolen it from Big Jupe).

All the actions you describe would take place with Sol's gravity E-well,
and should be conservative wrt Sol.  But Jupiter might provide some
supercharging. Actually, I'd guess you want a reasonably massive body
(mass >> body to accelerate) with as high an orbital velocity as possible.

Scott Bayes

I hope the above is correct...

------------------------------

End of SPACE Digest V9 #508
*******************